Semiconductor Bridge Research Articles

Characteristics of an antistatic semiconductor bridge based on micro/nano processing techniques

Abstract Regarded as a novel type of igniter, semiconductor bridge (SCB) prove superior in burst time and burst energy (less than 5 mJ). Nevertheless, SCB discharged by strong electrostatic discharge (ESD) inevitably leads to damage. To enhance the electrostatic safety of the semiconductor bridge initiator, an antistatic semiconductor bridge (ASCB) initiator incorporating a transient suppression (TVS) diode was fabricated based on micro/nan processing techniques. Three sizes of polysilicon bridge (10440 µm2, 17020 µm2, and 23760 µm2) and two breakdown voltages of TVS (7.3V and 8.6V) were designed. Then constant discharge test and ESD test were carried out to investigate the effects of bridge area and TVS breakdown voltage on the performance of ASCB. The results showed that, the energy density of polysilicon bridge is a linear function of the ratio of the square of the current to the area of the polysilicon (ISCB2/A). The breakdown voltage will affect the shunt of TVS. During polysilicon heat accumulation process, owing to shunt of TVS, the energy applied to the polysilicon bridge reduced. In addition , the bridge with a larger area were more difficult to reach the explosive limit. Therefore, both the breakdown voltage of the TVS and the area of the polysilicon bridge influenced the explosive characteristics of the ASCB. The antistatic performance of ASCB is obviously stronger than that of SCB, and A2 (ASCB with bridge area of 23760 µm2 and breakdown voltage of 7.3V) is the strongest among the three types of ASCB. Reducing the breakdown voltage of TVS and increasing the bridge area of polysilicon can effectively improve the antistatic performance of ASCB.

Considerable enhancement of nanothermites propagation through worm-like expansion of expandable graphite

Metastable intermolecular composites (MICs) are known for their high energy density, high burn rate, and low diffusion distance, and they have various applications in military and civilian equipment and tasks. However, the introduction of binders, which facilitate shaping, during the processing of MICs for practical applications can lead to a decrease in the energy release rate and an increase in the required ignition energy. Herein, we incorporated graphene nanoplatelets (GNPs), multi-walled carbon nanotubes (MWCNTs), and expandable graphite (EG) into 90- wt% Al/CuO nanothermites stick using simple extrusion-based direct ink writing to improve their overall performance. The high-temperature expansion characteristics and unique structure after expansion caused EG to perform an important role during Al/CuO nanothermites system combustion, which effectively promotes heat transfer and considerably increases the burn rate (81.6%) and pressure rising rate (103.0%). This study demonstrated EG as a low-cost and efficient combustion catalyst for MICs and introduced a simple approach to modulate the energy release rate, combustion pressure and semiconductor bridge (SCB) ignition performance of MICs through incorporation of small amounts of carbon materials.

3-D temperature measurement of transient plasma during semiconductor bridge electroburst with high-speed interferometry

A high-speed technique for three-dimensional (3-D) imaging of dynamic transient temperature field using single-shot off-axis interferometry is proposed. The sequence of interferograms, which contain temperature parameters of plasma, is obtained with using a Mach-Zender interferometer system and high-speed photography. The interferograms were processed using the Fourier transform and the Abel algorithm, to extract the refractive index distribution. Subsequently, the radial and 3-D distribution of temperature were derived with G-D equation. In experiments, transient process less than 100μs during plasma electroburst was successful captured at a frame rate of 3 × 106 fps. The 3-D temperature and its variations during the whole process in a SCB ignition was clearly revealed for the first time.

Effect of copper in the stabilization of Al/CuO energetic semiconductor bridge

The long-term storage performance of energetic multilayer nanofilms is of great significance for their applications. In this paper, it is proposed to add a 10 nm Cu barrier layer between Al/CuO composite films to increase their storage stability. The Al/CuO composite film and Al/Cu/CuO composite film were aged for 14 days in an environment with a relative humidity of 40% and a temperature of 71 °C. Scanning electron microscopy and differential scanning calorimetry were used to analyze the microstructure and thermodynamic properties of the energetic films before and after aging, and the electrical detonation performance and ignition ability of energy-containing semiconductor bridges were studied. The results indicate that after aging for 14 days in an environment with a relative humidity of 40% and a temperature of 71 °C, the Al layer of the Al/CuO composite film becomes thinner, the Al2O3 interface layer increases, and the heat release decreases. The interlayer microstructure of the Al/Cu/CuO energetic multilayer nanofilms did not change significantly, and the addition of a 10 nm Cu layer formed a low-temperature Al–Cu alloy, reducing the reaction initiation temperature from 626 to 570 °C. The critical ignition time and critical ignition energy of the Al/CuO-energetic semiconductor bridge (ESCB) increased, the flame duration shortened from 440 to 300 μs, the flame size decreased by 50%, the plasma temperature decreased, and aging had no significant effect on the electrical explosion performance of Al/Cu/CuO-ESCB. After aging for 14 days in an environment with a relative humidity of 40% and a temperature of 71 °C, the maximum ignition gap of B/KNO3 for Al/CuO-ESCB decreased from 1.4 to 1.2 mm, while the maximum ignition gap for Al/Cu/CuO-ESCB remained at 1.6 mm, which significantly improved the ignition performance and long storage performance of the energetic semiconductor bridge.

Enhancing the energy release performance of nanothermites through metal oxides free oxygen and pores

Efficient energy release and the large-scale preparation of thermite with high energy density are currently crucial issues in the field of explosive systems. In this study, we focused on the utilization of porous metal oxides (pMxOy) prepared through urea co-precipitation and high-temperature annealing to enhance the ignition and combustion performance of nanothermites. We compared the thermochemical reactivity, ignition, and combustion performance of nAl/pMxOy with those of nanothermites composed of nano metal oxides. We found that the use of pMxOy resulted in significantly increased the reaction exergy and reduced the activation energy of nanothermites, the energy released by the nanothermite containing pMxOy increased by up to 33.4%, while the activation energy decreased by up to 34.8%. Furthermore, the ignition and combustion results show that better semiconductor bridge ignition, pressurization, and combustion performance of nanothermites consisting of high free oxygen ratio and high porosity pMxOy. This improvement can be attributed to the enhanced contact between nAl and pMxOy, as well as the improved oxygen ionic conductivity of pMxOy. We believe that this high-performance nanothermite, which utilizes porous metal oxides exhibiting high interfacial activity, can be extensively employed in various initiating explosive devices. Notably, the simplicity of the batched preparation process further enhances its potential for practical application.

Identifying the enhancement mechanism of Al/MoO3 reactive multilayered films on the ignition ability of semiconductor bridge using a one-dimensional gas-solid two-phase flow model

Energetic Semiconductor bridge (ESCB) based on reactive multilayered films (RMFs) has a promising application in the miniature and intelligence of initiator and pyrotechnics device. Understanding the ignition enhancement mechanism of RMFs on semiconductor bridge (SCB) during the ignition process is crucial for the engineering and practical application of advanced initiator and pyrotechnics devices. In this study, a one-dimensional (1D) gas-solid two-phase flow ignition model was established to study the ignition process of ESCB to charge particles based on the reactivity of Al/MoO3 RMFs. In order to fully consider the coupled exothermic between the RMFs and the SCB plasma during the ignition process, the heat release of chemical reaction in RMFs was used as an internal heat source in this model. It is found that the exothermal reaction in RMFs improved the ignition performance of SCB. In the process of plasma rapid condensation with heat release, the product of RMFs enhanced the heat transfer process between the gas phase and the solid charge particle, which accelerated the expansion of hot plasma, and heated the solid charge particle as well as gas phase region with low temperature. In addition, it made up for pressure loss in the gas phase. During the plasma dissipation process, the exothermal chemical reaction in RMFs acted as the main heating source to heat the charge particle, making the surface temperature of the charge particle, gas pressure, and gas temperature rise continuously. This result may yield significant advantages in providing a universal ignition model for miniaturized ignition devices.

Design and performance of a micro-scale detonation train with a built-in pyrotechnic MEMS-based safety and arming device

To improve the equipment miniaturization and reliability of weapons and ammunition systems, this study designs a micro-scale detonation train (MDT) with a built-in pyrotechnic microelectromechanical system (MEMS)-based safety and arming (S&A) device, which consists of an energetic semiconductor bridge (ESCB) detonator, and a S&A device with built-in isolation mechanisms, and a micro-detonation train. Furthermore, this study investigates the effects of the slider thickness, the spring beams’ thickness, and the positioning beam type on the security of the S&A device using the Finite Element Dynamics software and verifies the function of the MDT through experiments of capacitive charge and discharge ignition. As indicated by the results, an encouraging arming function can be achieved under a slider thickness of 1.0 ​mm and a positioning beam type of PB, while the spring beam thickness is less relevant. Additionally, the results show that the arming function of the MDT can be completed in 0.6 ​ms.

Topology Optimization Design for Heat Dissipation Performance of Semiconductor Ignition Device

Abstract The trend of miniaturization and intgration of the electronic device has put forward higher requirements on efficiency of heat radiating, which can hardly be satisfied by the traditional forced convection heat dissipation method. In this paper, the strategy of topology optimization technique is adopted to greatly improve the heat dissipation efficiency of a semiconductor ignition device. The penalization method is used to implement the topology optimization process. Three kinds of objective functions of thermal compliance, temperature variance and geometric average temperature were separately applied in the topological optimization of two typical uniform heat generation cases, and the resulted topologically optimization results were analyzed and compared. Based on the two benchmark cases, the appropriate objective function was selected to conduct structural optimization of semiconductor bridge ignition devices with the aim of making the highest temperature in the design domain the lowest possible. Additionally, a parametric study on the effect of thermal conductivity on topology optimization results was conducted, which leads to a design suggestion beneficial for heat dissipation and material selection.

Design of initiating explosives for semiconductor bridge Primer for rapid-fire projectiles

Based on SCB (semiconductor bridge) chip technology, this paper designs a semiconductor bridge ignition component in the standard primer shell, and designs a primer prototype for the high instantaneous, high safety, and high consistency ignition requirements of the current rapid-fire projectiles for the primer of pyrotechnics. First of all, the design and study of a high instantaneous, insensitive SCB chip can meet the safety of 1A1W5min without fire, while reducing the fire time and fire energy; secondly, the research on the packaging technology of SCB chips is carried out. Combined with PCB or ceramic parts, a flat package structure is designed and matched with the standard primer structure. At the same time, the design and performance test of the semiconductor bridge primer for rapid-fire projectiles has been completed. The results show that the action time of the prototype the integrated primer is ≯200µs, and the dispersion is ≯30µs; compared with the current electric primer product, its safety, instantaneousness, and action time are more consistent, and the overall performance is better.

Semiconductor Bridge Temperature Change Study under Different Excitation Methods and Sizes

The temperature of the semiconductor bridge increases due to the Joule heat effect in the way of capacitive discharge voltage excitation and current excitation, but the temperature distribution and the effect of different excitation methods and different sizes on the temperature change are not very clear; aiming at this problem, the temperature distribution of the semiconductor bridge after electrical energy excitation is simulated by finite element simulation. The effects of excitation mode and bridge area size on the temperature rise process of the bridge were studied by the control variable method; finally, the high-temperature area of the bridge body is only distributed in the bridge area, the temperature of the bridge body is positively correlated with electrical energy but negatively correlated with the area of the bridge area, and the current excitation method is better than the effect of voltage excitation. In addition, the conclusion is that the appropriate increase in excitation energy and the reduction of bridge size can help the temperature rise to improve the efficiency of the semiconductor bridge in practical applications.

Preliminary discussion on the ignition mechanism of exploding foil initiators igniting boron potassium nitrate

Exploding foil initiator (EFI) is a kind of advanced device for initiating explosives, but its function is unstable when it comes to directly igniting pyrotechnics. To solve the problem, this research aims to reveal the ignition mechanism of EFIs directly igniting pyrotechnics. An oscilloscope, a photon Doppler velocimetry, and a plasma spectrum measurement system were employed to obtain information of electric characteristics, impact pressure, and plasma temperature. The results of the electric characteristics and the impact pressure were inconsistent with ignition results. The only thing that the ignition success tests had in common was that their plasma all had a relatively long period of high-temperature duration (HTD). It eventually concludes that the ignition mechanism in this research is the micro-convection heat transfer rather than the shock initiation, which differs from that of exploding foil initiators detonating explosives. Furthermore, the methods for evaluating the ignition success of semiconductor bridge initiators are not entirely applicable to the tests mentioned in this paper. The HTD is the critical parameter for judging the ignition success, and it is influenced by two factors: the late time discharge and the energy of the electric explosion. The longer time of the late time discharge and the more energy of the electric explosion, the easier it is to expand the HTD, which improves the probability of the ignition success.

Investigation on heat transfer mechanism of semiconductor bridge ignition based on thermoelectric coupling analysis

The heat transfer mechanism in the electroexploding ignition process of the semiconductor bridge (SCB) is studied by finite element simulation to reveal the ignition mechanism of SCB, and the ignition threshold voltage of SCB is predicted by the critical ignition heat Qc. The thermoelectric coupling model is adopted to analyze the distributions of temperature and electric field intensity for the SCB. Under the capacitor discharge of 30 V, the temperature distribution is not uniform of the bridge, and the temperature rises fastest at the "heat points" formed at the V-shaped sharp corners. The highest electric field intensity also appears first at the V-shaped sharp corners, and then the electric field intensity concentrates the edge of the melted zone greatly increasing the heat generation in the un-melted zone. Since the melted zone enlarges with the propagation of the electric field intensity, the heat transfer during the ignition process can be attributed to the coupling effect caused by the thermal and electric fields. After the Qc of SCB is calculated from the enthalpy value corresponding to the phase changes of melt and vaporization, the heat generation Qr-t curves are used to determine the ignition threshold voltage of 21 V for the specific size SCB device by comparing with the Qc value. This method could be used to predicate the ignition threshold voltage of the electroexploding ignition for various types of SCB, so it is very important for guiding the design of SCB in practical applications.

Modeling the Heating Dynamics of a Semiconductor Bridge Initiator with Deep Neural Network.

A semiconductor bridge (SCB) is an ignition device that provides a safe and efficient method widely used in civilian and military fields. The heating process of an SCB under electrical stimulation has a wide range of applications owing to its unique energy release process. However, the temperature variation of an SCB is challenging to obtain, both experimentally because of the rapid reaction on a microscale and with simulation due to its high demand in nonlinear calculations. In this study, we propose deep learning (DL) approach to study the electrothermal-coupled multi-physical heating process of the SCB initiator. We generated training data with multi-physics simulation (MPS), producing surface temperature distributions of SCBs under different voltages. The model was then trained with partial data in this database and evaluated on a separate test set. A generative adversarial network (GAN) with a customized loss function was used for modeling point-wise temperature dynamics. In the test set, our proposed method can predict the temperature distribution of an SCB under different voltages with high accuracy of over 0.9 during the heating process. We reduced the computation time by several orders of magnitude by replacing MPS with a deep neural network.

Modeling the heating dynamics of a semiconductor bridge ini-tiator with deep neural network

Modeling the heating dynamics of a semiconductor bridge ini-tiator with deep neural network

Aluminum/lead tetroxide nanothermites for semiconductor bridge applications

Renewed interest in exploiting the full potential of nanothermites has been observed, considering that typical nanothermite powders are prone to get agglomerated and react incompletely. Herein, via direct ink writing, the fabrication of nanothermite films and their integration on semiconductor bridges come true simply and efficiently, keeping nanoscale agents spatially uniform and therefore chasing for reinforced output capability. The key ingredients are Al/Pb3O4 nanothermites and such ink formulation features higher particle loading (95 wt%) than that previously reported in the literature. Experimental results show that the maximum output energy of the Al/Pb3O4 nanothermite inks reaches 1960 J g−1, while the average linear burning rate maintains nearly 19.14 cm s−1. Furthermore, the lab-on-a-chip integration of nanothermite films prominently enhances the energy yield of semiconductor bridges (up to 282 mJ). It turns out that Al/Pb3O4 nanothermite inks show great potential for applications on semiconductor bridges due to their remarkable output performance.

Coaxial electrospinning fabrication of core-shell energetic fibers and in-situ integration with SCB exhibiting superior non-contact ignition

Electrospinning has exhibited great potential in the fabrication of fibrous energetic materials for the past few years. Herein, the core–shell energetic fibers (defined as CSEF) were designed and fabricated through the coaxial electrospinning. The core stratum was Al/MoO3-PVDF and the shell stratum was CL-20-NC. The morphologies of CSEF performed a clear core–shell structure, and the constituent analyses demonstrated that the components did not change after the preparation. According to the relative content of CL-20, the samples were defined as CSEF0C, CSEF10C, CSEF30C and CSEF50C respectively. The clear core–shell structure of CSEF was confirmed through the morphologies. The total heat releases of CSEF were not affected by the variation of the content of CL-20 nearly, and the existence of CL-20 improved the thermal stability of Al/PVDF. The combustion propagation velocity of CSEF increased by the increase of CL-20 from 0.241 m/s (CSEF0C) to 0.664 m/s (CSEF50C). In addition, CL-20 decreased the ignition temperature and delay time of CSEF. The combustion products analyses demonstrated that CL-20 promoted the combustion performance of CSEF by leading to less sintering of the reactants. Furthermore, CSEF50C films were fabricated and deposited onto a semiconductor bridge (SCB) in-situ (defined as CSEF50C-SCB). CSEF50C-SCB possessed larger flame and longer combustion duration, which displayed an excellent clearance ignition ability. The superior combustion performance of CSEF films assembled with SCB in-situ would exhibit the admirable application prospects for practice when combined the Micro-electromechanical systems (MEMS).

Characteristics of micro energetic semiconductor bridge initiator by depositing Al/MoO3 reactive multilayered films on micro bridge with different bridge size

Four types of Al/MoO3 micro energetic semiconductor bridge (MESCB) initiators were prepared by integrating 3 µm Al/MoO3 reactive multilayer films (RMFs) on micro semiconductor bridge (MSCB) with different bridge areas. The bridge areas were varied from 11661 µm2 to 489 µm2, and the ratio of length to width, the thickness, V-type angle were fixed at 0.54, 2.5 µm, 90°, respectively. The heating process of MSCB before electrical explosive was analyzed with multi physical simulation (MPS). The electrical explosive characteristics of these MESCB as well as MSCB were investigated under the stimulation of 47 µF tantalum capacitor discharge. The MPS results reveal that the V-shaped sharp corner of MSCB has highest temperature and the completed melting time of MSCB is decreased with lowing of bridge area. The critical burst time and critical burst energy of MSCB and MESCB also decrease with the decreasing of bridge area. When bridge area is 11661 µm2, the critical burst time of MSCB and MESCB drops with applied voltage, while critical burst energy is independent on applied voltage. Besides, the critical burst time and energy of MESCB are the higher than that of MSCB with bridge area of 11661 µm2. When the bridge area is reduced to 2915 µm2, the critical burst time and critical burst energy for MESCB are no significant difference with the corresponding MSCB. In addition, the critical burst time MSCB and MESCB have no relationship with outer stimulation energy as the bridge area further decrease at 489 µm2. The flame duration time of MESCB barely decreases when lowing the bridge area, which suggests that the energy consumption of MESCB can be reduced by decreasing the bridge area without weakening its firing performance.

An ultrafast temperature response analysis of a MEMS-based igniter using the finite-element method

This study reports the simulation and experiments of a MEMS-based igniter for a semiconductor bridge (SCB), which is fabricated using complementary metal oxide semiconductor technology. The finite-element method was first employed to simulate the ultrafast temperature response of the ignition process of SCB under conditions of an electro-exploding ignition, electro-thermal ignition, and no-ignition and to conduct a capacitor discharge stimulation. The recorded voltage from an oscilloscope was used as the initial condition, and conductivity values based on experimental data were taken as a key parameter for the polysilicon material to ensure the accuracy of the heat source loaded into the model. Under the electro-exploding ignition, the SCB was initially ignited at the sharp corners at the valley of the first voltage peak instead of the secondary peak. The maximum temperature of the SCB was no more than the melting point of the polysilicon material (except for the sharp corners) and only at 1369 ​K under the electro-thermal ignition and no-ignition conditions, respectively. The optical testing and ablation results of the bridge area demonstrate that the numerically simulated temperature is quite accurate. This method can be easily extended to other MEMS-based igniters for temperature prediction applications.

Investigation on Heat Transfer Mechanism of Semiconductor Bridge Ignition Based on Thermoelectric Coupling Analysis

Investigation on Heat Transfer Mechanism of Semiconductor Bridge Ignition Based on Thermoelectric Coupling Analysis

Research of the Characteristics of Semiconductor Bridge (SCB) Plasma

A better understanding of semiconductor bridge (SCB) discharge behavior under different firing conditions was crucial to revealing the mechanism of the SCB ignition technique. In this paper, the tests on the basic parameters, including the onset time, duration time, temperature, and electron density of SCB plasma, were carried out. A simpler and more economical system was used to discuss the characteristics of SCB plasma under the different input energy conditions.